This is just what I have been looking for. One feature that might work, I plan off road trips as well as other types, it a feature that allows users to upload GPX files so the group can upload those too. Google isn't the best for those trips as an end result, but a great tool for the initial planning and allowing people to see where they are going.

There might be security issues with file uploads and maybe that is why you don't have it. Just a thought.